Automatic billet center punching machine



May 28, 1963 w. R. JACKSON 3,091,139

AUTOMATIC BILLET CENTER PUNCHING MACHINE Filed April 8, 1960 4 Sheets-Sheet 1 n V w m a T G N N J R. :V.. O N R n I m A m% H 4- w 7 E w UH I 8 .1 wk mlm mm, ow m2 3 Fl m2 mm mm, mm, mm, w, NNN Mm T IBM-w \m/ E g flu llmm. I -Q i 8 @9 Ill. 08 N g mm mm mm 3 3w w\ Ll 4 Sheets-Sheet 2 W. R. JACKSON AUTOMATIC BILLET CENTER PUNCHING MACHINE Filed April 8. 1960 May 28, 1963 INVENTOR William R Jackson. 7

ATTORNEY May 28, 1963 w. R. JACKSON AUTOMATIC BILLET CENTER PUNCHING MACHINE Filed April 8, 1960 4 Sheets-Sheet 5 INVENTOR 3:7. Jackson.

William 8Y7 mON ATTORNEY May 28, 1963 i w. R. JACKSON 3,091,139

AUTOMATIC BILLET CENTER PUNCHING MACHINE Filed April 8, 1960 4 Sheets-Sheet 4 INVENTOR William R. Jackson.

ATTORNEY United States Patent ()ffice 3,591,139 Patented May 28, 1963 William Roland Jackson, Youngstown, Ohio, assignor to Fordees Corporation, Leetonia, Ohio, a corporation of Ohio Filed Apr. 8, 1960, Ser. No. 20,862 6 Claims. (Cl. 78-9) This invention relates to apparatus for punching centering holes in the ends of hot metal billets, and more particularly to apparatus of the type described for punching holes in the ends of hot steel billets preparatory to a seamless tube forming operation.

In the manufacture of tubular products by the seamless process, it is necessary to initially produce a hole in the end of a heated metal billet at the center thereof preparatory to a piercing operation. In the past, this bore was usually provided by means of a pneumatically operated punch or the like which Was repeatedly forced against the end of the billet in a forging operation until a hole of the desired depth was formed. It is of vital importance that this hole be located at the exact center of the billet, and since billets of different diameters were punched on the same machine, a vertically adjustable table structure was provided for supporting the billet during a punching operation, the arrangement being such that the table could be raised or lowered to accommodate billets of different diameters whereby the longitudinal axis of any billet could be aligned with the longitudinal axis of the punch.

One difliculty with machines of the type described above, however, is that the depth of the centering hole which can be produced with a pneumatic hammer is limited and unsatisfactory for certain piercing operations. In addition, it is oftentimes difficult to exactly align the billet with the punch, with the result that the bore is sometimes misaligned with respect to the longitudinal axis of the billet. Further, in prior art machines of the type described above, the end of the billet opposite the punch was supported against a stop, and the forward thrust of the billet during a punching operation was obsorbed by this stop. With this arrangement, it was necessary to secure or clamp the entire length of the billet between the stop and the punch to prevent it from buckling under the impact of the punch. This is a rather cumbersome arrangement and requires a more or less complicated clamping and holding mechanism. Still another disadvantage of such prior art punching machines resides in their relatively slow operational cycle which permits not more than about two hundred billets per hour to be punched. Such a slow operational cycle is, of course, due to the fact that a considerable amount of time is required to permit the reciprocating pneumatic hammer to form a hole of the proper depth.

As an overall object, the present invention seeks to provide a new and improved billet center punching machine in which the punch is actuated by a hydraulic cylinder whereby much greater punching pressures can be achieved over a pneumatic hammer arrangement, resulting in greater depths of the centering holes as are required in certain piercing operations.

Another object of the invention is to provide a hydraulic billet center punching machine in which only the end of the billet adjacent the punch is secured by a single clamping device, thereby obviating the necessity for clam-ping devices disposed along the entire length of the billet as in prior art devices.

Another object of the invention resides in the provision of a self-centering clamping device for a billet center punching machine which will automatically align the billet with a reciprocating punch, thereby making it unnecessary to align the billet by carefully and exactly adjusting the height of a table or cradle structure on which the billet is supported.

Still another object of the invention is to provide hydraulic billet center punching apparatus capable of achieving a much higher production rate than punching machines of the type previously used.

In accordance with the invention, hereinafter described, there is provided a horizontally disposed hydraulic cylinder having a piston therein. Secured to the piston is a ram or punch adapted to be reciprocated by the piston along a straight line horizontal path, and beyond the forward end of the piston is a cradle or table structure adapted to support a billet in general alignment with the punch. At the end of the cradle structure adjacent the punch is a self-centering clamping device comprising a pair of opposing jaws between which the billet is secured during a punching operation. The clamping device is such that the aforesaid opposing jaws are actuated by a single hydraulic cylinder operatively connected to the jaws through a pair of rocker arms disposed on either side of the billet and adapted to maintain the opposing jaws at equal distances from the center line of the punch at all times. With this arrangement, the billet will be automatically and exactly aligned with the punch when it is clamped between the jaws regardless of the height of the aforesaid cradle structure or any deviation in billet diameter. At the same time, since the billet is clamped immediately adjacent the punch, the forward thrust of the billet during a punching operation may be absorbed by the aforesaid jaws, and no possibility exists of deflection of the billet along its length.

The above and other objects and features of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings which form a part of this specification and in which:

FIGURE 1 is a side view of the overall billet center punching apparatus of the invention;

FIGURE 2 is a sectional view of the apparatus taken along line -IIII of FIGURE 1, illustrating the operation of the cradle structures for supporting a billet during a punching operation;

.FIGURE 3 is a detailed cross-sectional view taken along line IIIIII of FIGURE 1 showing the details of the self-centering clamping mechanism of the invention; and

FIGURE 4 is a cross-sectional view taken along line IV-IV of FIGURE 2.

Referring to FIGURES 1 and 2, the apparatus of the inventi-on is supported on a floor or base structure 10 and includes a pair of parallel upright I-beams 12 and 14- which carry a billet supporting and manipulating structure, generally indicated at 16. As is best shown in FEGURE 2, the billet supporting and manipulating structure includes a plurality of I-beams l8 spaced along the length of the beams 12 and 14 and extending therebetween. The I- beams 18 may be welded or otherwise securely fastened to the beams 12 and 14 and carry a plurality of spaced structures 20 and 22 each of which has a vertically extending guideway therein. As will be understood, each beam 18 carries a pair of the structures 20 and 22 to provide a pair of facing guideways within which is disposed a vertically reciprocable block 24. The blocks 24 on the respective beams 18 spaced along the length of the assembly are interconnected by means of a channel member 26 which, in turn, may be raised or lowered by means of a plurality of jacks 28. As shown, the jacks 28 are all driven from a common shaft 30 by means of worm gears 32. Thus, when the shaft 30 is rotated in one direction, the channel member 26 and the various blocks 24 will be elevated in the guideways in members 20 and 22; whereas, rotation of the shaft 30 in the opposite direction will lower the blocks 24. Extending through the various blocks 24 is a shaft 34 having a plurality of billetsupporting cradle structures 36 keyed or otherwise securely fastened thereto. As will be understood, the shaft 34 may be rotated in a clockwise direction whereby a billet B supported on the cradle structures 36 will be transferred to run out skids 38 where it will roll onto a conveyor or the like, not shown, which conveys the billet to a remote point. An unpunched billet is disposed on skids 40 and comes to rest against stop members 42. The stop members 42 are spaced along the length of the billet-supporting and conveying structure and are carried on rotatable shaft 44, the arrangement being such that when the stop members 42 are in the position shown, the entering billet will be prevented from rolling onto the cradle structures 36. When, however, the shaft 44 is rotated in a clockwise direction, the waiting billet will be permitted to roll onto the cradle structures 36. After one billet has been transferred to the cradle structures 36, the shaft 44 will be rotated in a counter-clockwise direction whereby the next successive billet will come to rest against surfaces 45 on the stop members 42 preparatory to its being transferred onto the cradle structures 36.

The billets on cradle structures 36 must be generally aligned with .a reciprocable punch, hereinafter described; and, since the diameters or cross-sectional configurations of the billets may vary, the height of the cradle structures 36 may be adjusted by the jacks 28 to substantially align the billet with the center line of the punch. As will hereinafter become apparent, however, the positioning of the billet B on the cradle structures 36 is not critical since the billet will be automatically centered or aligned with the punch by a clamping mechanism, generally indicated at 48.

Disposed in a recess in the floor or base at one end of the billet supporting and conveying structure 16 is a pedestal '50 (FIGURE 1) fabricated from angle irons or the like which supports a pair of parallel upright plates 52 and 54. Supported on the upper surfaces of plates 52 and 54, and a column 56 at the left end of the apparatus, is an elongated I-beam 60 which forms a guideway or track for a billet pushing carriage, generally indicated at 62. As shown, the billet pushing carriage 62 is formed from a pair of vertically extending plates 66 which are interconnected above and below the track or I- beam60 by blocks to provide an opening through which the track may pass. Carried on the plates 66 are rollers 68 adapted to travel along the lower flanges of the I-beams 60 whereby the carriage 62 may be reciprocated back and forth along the track. Depending downwardly from the plates 66 is an arm 70 having a member 72 at its lower extremity adapted to engage the end of a billet disposed on the cradle structures 36 and force it to the right as shown in FIGURE 1. To actuate the carriage 62 and arm 70, there is provided an elongated hydraulic cylinder 74 having its piston rod 76 connected to the carriage 64, substantially as shown. With this arrangement, the cylinder 74 may be pressurized to move the carriage 62 to the right and thereby force the billet on cradle structures 36 to the right. At the completion of a pushing operation, then, the carriage 62 may be returned to its initial position at the left-hand end of the assembly by pressurizing the opposite side of cylinder 74.

Extending between the four corners of plates 52 and 54 at the right-hand end of the assembly as shown in FIGURE 1, are four columns having their opposite ends threaded to receive tightening nuts 78 thereon. As will be understood, only two of the columns 80 and 82 are shown in FIGURES 1 and 4, it being understood that the other two columns are directly behind the columns 80 and 82 on the other side of the assembly. Flexible 4 bellows 8'1 and 83 (FIGURE 4) encircle the columns as shown to prevented dust and the like from depositing on their surfaces. Carried on the columns extending between the plates 52 and 54 is a third plate 84 which may be reciprocated on the columns by means of hydraulic cylinders 86 and 88 carried on the plate 54.

As best shown in FIGURE 4, the four corners of the plate 84 have bores 90 therein, with each of the bores being provided with a bushing 92 which slides on the surface of one of the columns extending between plates 52 and 54. Also carried on the plate 54 is a horizontally disposed hydraulic cylinder 94 having a piston, not shown, reciprocable therein. Connected to the piston of cylinder 94 is a piston rod 96 which carries, at one end, a pointed punch 98 adapted to be forced into the end of a billet positioned on the cradle structure 36. In a punching operation, an end of the billet will be held between the opposing jaw-s 100 and 102 of the clamping mechanism 48. After the billet is clamped between the jaws 100- and 102, the cylinder 94 will be pressurized to move piston rod 96 and the punch 98 to the left as shown in FIG URE 4 whereby the punch will pass through opening or aperture 104 in plate 52 and into the end of the billet held between the jaws i100 and 1.02. Surrounding piston rod 96 and the punch 98 is a tubular member 106 which is carried on the plate 84, the arrangement being such that the member 106 may be moved independently of the punch 98 by press-urizing the cylinders 86 and 88. After a billet between jaws 100 and 102 is punched, the jaws 100 and 102 will be released. Thereafter, the cylinders 86 and 88 will be pressurized to move the plate 84 and tubular member 106 to the left as shown in FIGURE 4.

In this process, the member 106 will engage the forward end of the punched billet and will force it outof the respect to the tubular member 106 is provided by virtue of the fact that the enlarged diameter portion 112 of the piston rod may move forwardly in chamber 114 provided in the tubular member 106 before striking the shoulder 116'.

Referring to FIGURES 3 and 4, it will be seen that the clam-ping jaws 100 and 102 are carried in' vertically disposed guideways 118 and 120 which are welded or otherwise securely fastened to the left-hand side of plate 52 as viewed in FIGURES 1 and 4. The guideways 118 and 120 are maintained in a rigid position by means of gussets 122 which are welded to the plate 52 and guideway 118 or 120, respectively. As shown, each of the opposing jaws 100 and 102 is provided with slots or guideways 124 and 126, respectively, which are adapted to receive inserts 128- and 130 having circular surfaces 132 and 134 thereon adapted to' accommodate billets of different diameters, it being understood that the inserts '128 and 130 may be changed for each billet diameter or cross-sectional configuration. As shown in FIGURE 3, the inserts 128 and 130 are held in place by mean-s of plates 136 and 138 which are secured to the opposing jaws 100 and 102 by means of bolts 140 or other similar fastening means. The ends of jaws 100 and 102 opposite the inserts 128 and 130 are provided with rectangularly shaped recesses 142 and 144 which receive bronze plates 146 and 148.

The bronze plates 146 and 148 provide bearing surfaces between the jaws 100 and 102 and bearing blocks 150 and 152. The blocks 1% and 152, in turn, have curved bearing surfaces 156 and 158 for the reception of a pair of pins or axles 160 and 162. As is best shown in FIG- URE 4, the pins '160 and 162 have their opposite ends supported in bearing blocks 164 and 166. The bearing blocks 166 are carried within apertures in extensions 168 and 170 n he jaws 100 and 10.2. The b a n blocks 164, on the other hand, are carried in apertures provided in plates 172 and 174 which are bolted to the outside surfaces of jaws 100 and 102 as by means of bolts 176 or other suitable fastening means. The pins .160 and 162 are held on the bearing surfaces 156 and 158 in bearing blocks 150 and 152 by a first pair of opposing ends 178 and 180 of clamp arms 182 and 184, best shown in FIGURE 3.

With reference to FIGURE 3, it will be noted that a pair of pivot pins 186 and 188 extend outwardly from the upright plate 52 with their axes being parallel to each other. The extremities of the pins 186 and 188 are interconnected by means of an elongated plate 187. Pivotally connected to the pivot pins 186 and 188 intermediate their ends are the clamp arms 182 and 184, the arrangement being such that when the opposing ends 178 and 180 of the clamp arms move together the other pair of opposing ends 190 and 192 will move apart and vice versa. As best shown in FIGURE 1, pins 194 and 196 extend through the opposing ends 190 and 192 and are interconnected by a pair of coil springs 198 and 200 which tend to pull the ends 190 and 192 together.

Referring again to FIGURE 3, the ends 190 and 192 of clamp arms 182 and 184 are provided with a pair of pivot pins 202 and 204 which carry a pair of bearing blocks 206 and 208. These bearing blocks, in turn, ride on the opposing inclined surfaces 210 and 212 of a double wedge-shaped member 214. The double wedge shaped member 214 is carried at the end of the piston rod of a hydraulic cylinder and piston arrangement 216 which is disposed midway between the axes of pivot pins 186 and 188. It will be noted that the inclined surfaces 210 and 212 are disposed at equal angles with respect to the longitudinal axis of the hydraulic cylinder 216 which, as was mentioned above, is midway between the pivot pins 186 and 188. With this arrangement, the bearing blocks 206 and 208 as well as the ends 190 and 192 will always be at equal distances from the center line or longitudinal axis of the hydraulic cylinder 216, and since this center line intersects the center line of the punch 98, the ends 190 and 192, as well as the ends 178 and 180, will also be at equal distances from the center line of punch 98. Similarly, the jaws 100 and 102, as well as the inserts 128 and 130, will likewise be at equal distances from the center line of the punch at all times. Consequently, whenever a billet is disposed between the jaws 100 and 102, and the wedge-shaped member 214 forced to the right as shown in FIGURE 3, the ends 190 and 192 will move apart while the'jaws 108 and 102 will move together to clamp the billet in a position where its longitudinal axis is exactly aligned with the longitudinal axis of the punch 98. Thus, when the punch 98 is moved forwardly into the end of the billet by cylinder 94, it will produce a hole in the end of the billet at its exact center. When the wedge-shaped member 214 is retracted to the left as shown in FIGURE 3, the springs 198 and 200 will pull ends "190 and 192 together, thereby separating the jaws 100 and 102. A stop member 220 extends outwardly from plate 52 and is adapted to limit movement of the wedge-shaped member 214 to the right as shown in FIGURE 3.

In the operation of the device, billets on skids 40 will be conveyed one by one over the stop member and onto cradle structures 36. When a billet is positioned on the cradle structures 36, it will actuate a limit switch, not shown, which will, in turn, actuate the hydraulic cylinder 74 to move carriage 62 to the right as shown in FIGURE 1. This will force the end of the billet adjacent the clamping device 48 into the space between jaws 100 and 102. After the carriage 64 has moved to the right in an amount suflicient to insert the end of the billet into the space between jaws 100 and 102, a second limit switch will be actuated which will cause the carriage 64 to be retracted to the left as shown in FIGURE 1. At the same time, the hydraulic cylinder 216 will be 6 pressurized to force wedge-shaped member 214 to the right as shown in FIGURE 3, thereby forcing apart opposing ends 190 and 192 while forcing clamping jaws and 102 together to secure the billet disposed therebetween. This action will continue until the pressure supplied to cylinder 216 reaches a predetermined value,

at which point a pressure switch, not shown, will be actuated to shut off the supply of fluid pressure to cylinder 216 and thereby stop movement of wedge-shaped member 214 to the right as shown in FIGURE 3. With this arrangement, a predetermined pressure can be maintained on the jaws 100 and 102, and this pressure will be just sufficient to hold the billet between the jaws during a punching operation without crushing the same.

At the same time that movement of double wedgeshaped member 214 is stopped, the cylinder 94 will be pressurized to move piston rod 96 and ram 98 to the left as shown in FIGURE 4. In this process, the ram 98 will be forced into the center of the billet to form a hole therein. After the ram 98 has moved into the billet by a predetermined amount, another limit switch, not shown, will be actuated by a projection on rod 222 carried on piston rod 96 (see FIGURE 4). Actuation of this latter-mentioned limit switch will then cause pressurization of the cylinder 94 in the opposite direction to retract the piston rod 96 and punch 98. At the same time, the cylinder 216 will be pressurized to move wedge-' shaped member 214 to the left as shown in FIGURE 3 whereby the springs 198 and 200 will separate the clamping jaws 100 and 102 to release the billet held therebetween.

After the ram 98 has been retracted by the cylinder 94, still another limit switch, not shown, will be actuated by a projection on the rod 222 to pressurize cylinders 86 and 88 and move plate 84 to the left as shown in FIG- URE 4. This Will cause the tubular member 106 to move through aperture 104 in plate 52 and into the space between jaws 100 and 102, thereby pushing the punched billet out of the space between the jaws. Thereafter, the cradles 36 will be rotated in a clockwise direction as shown in FIGURE 2 to place the punched billet on the run-out skids 38 where it may roll onto a conveyor, not shown. Finally, the cradle structures 36 will be rotated in a counter-clockwise direction into the positions shown in FIGURE 2 where the next successive billet may be rolled onto the cradle structures by actuation of the stop members 42, and the cycle is repeated.

Although the invention has been shown in connection with a certain specific embodiment,it will be readily apparent to those skilled in the art that various changes in form and arrangement of parts may be made to suit requirements without departing from the spirit and scope of the invention. a

I claim as my invention:

1. In a billet center punching machine, a horizontally I disposed cylinder having a piston reciproeable therein, an

elongated piercing ram having one end connected to said piston and adaptedto be reciprocated by the piston along a straight line horizontal path, a cradle structure adapted to support a billet in alignment with said piercing ram whereby the end of the ram opposite said piston may be forced into an end of said billet at the center thereof, a single pair of opposing jaws at one end of the cradle structure for clamping only the end of said billet adjacent said piercing ram, means for conveying a billet onto v billet adjacent the piercing ram will be moved out of the space between said opposing jaws.

2. In a billet center'pun'ching machine, a base member, first and second upright parallel plate members carried on said base member, horizontallyexten'ding columns interconnecting said first and second plate members, a third upright plate member reciprocable on said columns for horizontal movement between said first and second plate members, a horizontally disposed cylinder carried on the first plate member, said cylinder having a piston reciprocable therein, an aperture in said second plate member, an elongated piercing ram having one end cona single pair of opposing jaws carried by said second plate.

member at one end of the cradle structure for clamping only the end of the billet adjacent said piercing ram, means for conveying a billet onto said cradle structure whereby its end adjacent the piercing ram will not extend into the space between said clamping jaws, means for pushing a billet on the cradle structure toward said second plate member whereby one end of the billet will extend into the space between said jaws, means for actuating said opposing jaws whereby they will clamp 'the end of a billet disposed therebetween, and a tubular member encircling said piercing ram and carried by said third plate member whereby the third plate member may be moved along said columns to force the tubular memher through the aperture in said second plate member and into the space between said jaws at the completion of a piercing operation to force the end of the billet held between the jaws out of the space between said jaws.

3. In a billet center punching machine, a horizontally disposed hydraulic cylinder having a piston reciprocable therein, an elongated piercing ram having one end connected to said piston and adapted to be reciprocated by the piston along a straight line horizontal path, a cradle structure adapted to support a billet in [alignment with said piercing ram whereby the end of the ram opposite said piston may be forced into an end of said billet at the center thereof, a single pair of opposing jaws at one end of the cradle structure for clamping only the end of said billet adjacent said piercing ram, means for actuating said opposing jaws whereby they will always be at equal distances from the longitudinal axis of said piercing ram, and a member coaxial with said piercing ram and adapted to be moved into the space between said opposing jaws at the completion of a piercing operation whereby said end of the billet adjacent the piercing ram will be moved out of the space between the opposing jaws.

4. The combination claimed in claim 3 wherein the cradle structure is adjustable in height to align the longitudinal axes of billets of various cross-sectional areas with the longitudinal axis of said piercing ram. I

5. In a billet center punching machine, a base .membet, a pair of parallel upright plate members secured to the base member, a horizontally disposed cylinder carried on one of said plate members and having a piston reciprocable therein, a centrally disposed opening in the ing said piercing ram and adapted to be moved into the other of said upright plate members, an elongated piercin g ram having one end .connected to. said piston and adapted to be reciprocated by the piston along a straight line horizontal path whereby its other end may be moved through the centrally disposed opening in said other up right plate member, a cradle structure disposed on the side of said other upright plate member opposite said piercing ram and adapted to support a billet in alignment with said piercing ram whereby the end of the ram opposite said piston may be forced into an end of said billet at the center thereof, a single pair of opposing jaws carried on said other upright member at one end of the cradle structure for clamping only the end of said billet adjacent said piercing ram, means for pushing a billet 'along the cradle structure whereby said end of the billet adjacent the piercing ram will be moved between said pair of opposing jaws, means carried on said other up-- right member for actuating said opposing jaws whereby they will always be at equal distances from the longitu- ;dinal axis of said piercing ram, and a tubular member surrounding said piercing ram and adapted to be moved into the space between said opposing jaws at the completion of a piercing operation whereby said end of the billet adjacent the piercing ram will be moved out of the ;:space between said opposing jaws.

6. In a billet center punching machine, a horizontally disposed hydraulic cylinder having a piston reciprocable therein, an elongated piercing ram having one end conneoted to said piston and adapted to be reciprocated by the piston along a straight line horizontal path, means for supporting said ram at a fixed vertical position, a cradle structure adapted to support a billet in alignment with said piercing ram whereby the end of the ram opposite said piston may be forced into an end of said billet 7 at the center thereof, a single pair of opposing jaws vertically movable toward and away from each other at one end of the cradle structure for clamping only the end of said billet adjacent said piercing ram, means for actuating said opposing jaws whereby they will always be at equal distances from the longitudinal axis of said piercing ram, means for pushing .a billet along the cradle structure whereby said end of the billet adjacent the piercing ram will be moved between said pair of opposing jaws when they are separated, and a tubular member surroundspace between said opposing jaws at the completion of a piercing operation whereby said end of the billet adjacent the piercing ram will be moved out of the space between said opposing jaws.

References Cited in the file of this patent UNITED STATES PATENTS 1,112,486 Germany Aug. 10, 1961 

1. IN A BILLET CENTER PUNCHING MACHINE, A HORIZONTALLY DISPOSED CYLINDER HAVING A PISTON RECIPROCABLE THEREIN, AN ELONGATED PIERCING RAM HAVING ONE END CONNECTED TO SAID PISTON AND ADAPTED TO BE RECIPROCATED BY THE PISTON ALONG A STRAIGHT LINE HORIZONTAL PATH, A CRADLE STRUCTURE ADAPTED TO SUPPORT A BILLET IN ALIGNMENT WITH SAID PIERCING RAM WHEREBY THE END OF THE RAM OPPOSITE SAID PISTON MAY BE FORCED INTO AN END OF SAID BILLET AT THE CENTER THEREOF, A SINGLE PAIR OF OPPOSING JAWS AT ONE END OF THE CRADLE STRUCTUR FOR CLAMPING ONLY THE END OF SAID BILLET ADJACENT SAID PIERCING RAM, MEANS FOR CONVEYING A BILLET ONTO SAID CRADLE STRUCTURE AT A POINT REMOVED FROM THE CLAMPING JAWS, MEANS FOR PUSHING A BILLET ALONG THE CRADLE STRUCTURE WHEREBY SAID END OF THE BILLET ADJACENT THE PIERCING RAM WILL BE MOVED BETWEEN SAID PAIR OF OPPOSING JAWS, MEANS FOR ACTUATING SAID OPPOSING JAWS WHEREBY 